don't know if this is a server-side or client-side bug, so I'm posting it here... if it's client-side, it's the Beta5 client; fel free to move it.

Hard to really describe, so here's a screenie:
note the discrepency between where the mining beam hits the roid, and where the debris is spewed up from the roid's surface.

Was that a rotating roid?

I don't think so, and even if it was, the phenomenon was widespread - all of the roids/bots in the sector were doing it